Interpolate motion between motion track keyframes
Tracking is an art. Perfect automatic tracking is hardly ever possible and will require some manual supervision and/or interpretation.

For a few frames you can manually move the tracking points in the tracking graph (that green and red graph that gives you the speed at which the trackcers are moving in the horizontal (red) and vertical (green) axis)

Other things to try: animate the settings for weight and stab weight. Or bring down the coorelation when tracking fast moving objects and bringing it up again when the motion slows down. And of course you can always use the clean-up tools in the solve tab.